This invention relates to a disengageable friction coupling for mounting an element on a shaft. It is intended to be used in a clutch or a brake mechanism.
Most clutch/brake mechanisms are very complicated, having a large number of parts, many of which are movable. A typical approach uses pads of friction material (U.S. Pat. No. 4,440,278 issued Apr. 3, 1984 to H. Weber for "Clutch and Brake Device for Presses, Punches and the Like") that are engaged or disengaged by axial movement under fluid pressure to contact rotating or stationary elements. Another approach exemplified by U.S. Pat. No. 3,835,971 issued Sept. 17, 1974 to E. A. Spanke, et al. for "Fluid Operated Clutch and Brake" uses interleaved wet plates that are alternately engaged and disengaged by axial movement of operating elements. The axial movement to engage or disengage the pads or discs is usually provided by hydraulic or pneumatic driven pistons incorporated into the clutch/brake mechanism.
These mechanisms are difficult to assemble and disassemble, and the presence of a large number of moving parts provides many points at which failure can occur. The mechanisms also typically require the continuous application of fluid pressure to maintain an engaged or disengaged attitude.